/*
 * The contents of this web application are subject to the Mozilla Public License Version 
 * 1.1 (the "License"); you may not use this web application except in compliance with 
 * the License. You may obtain a copy of the License at http://www.mozilla.org/MPL/.
 * 
 * Software distributed under the License is distributed on an "AS IS" basis, 
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
 * for the specific language governing rights and limitations under the License.
 * 
 * The Original Code is owned by and the Initial Developer of the Original Code is 
 * Composite A/S (Danish business reg.no. 21744409). All Rights Reserved
 * 
 * Section 11 of the License is EXPRESSLY amended to include a provision stating 
 * that any dispute, including but not limited to disputes related to the enforcement 
 * of the License, to which Composite A/S as owner of the Original Code, as Initial 
 * Developer or in any other role, becomes a part to shall be governed by Danish law 
 * and be initiated before the Copenhagen City Court ("K�benhavns Byret")            
 */

using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Xml.Linq;
using Composite.Core.Configuration;
using Composite.Core.IO;
using Composite.Core.Xml;

namespace Composite.Core.PackageSystem.PackageFragmentInstallers
{
    /// <summary>    
    /// </summary>
    /// <exclude />
    [System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Never)] 
    public sealed class ConfigurationTransformationPackageFragmentUninstaller : BasePackageFragmentUninstaller
	{
        private const string _uninstallElementName = "Uninstall";
        private const string _xsltFilePathAttributeName = "xsltFilePath";

        /// <exclude />
        public override IEnumerable<PackageFragmentValidationResult> Validate()
        {
            List<PackageFragmentValidationResult> validationResults = new List<PackageFragmentValidationResult>();

            ConfigurationTransformationPackageFragmentInstaller.ValidateXslt(
                validationResults,
                () => this.UninstallElement,
                _uninstallElementName,
                () => this.UninstallElement.Attribute(_xsltFilePathAttributeName),
                () => this.UninstallXsltFilePath,
                this.UninstallerContext.ZipFileSystem,
                true);

            return validationResults;
        }


        /// <exclude />
        public override void Uninstall()
        {
            using (Stream xsltFileStream = this.UninstallerContext.ZipFileSystem.GetFileStream(this.UninstallXsltFilePath))
            {
                using (TextReader xsltTextReader = new C1StreamReader(xsltFileStream))
                {
                    XDocument xslt = XDocument.Load(xsltTextReader);

                    ConfigurationServices.TransformConfiguration(xslt, false);
                }
            }
        }


        private XElement UninstallElement { get { return this.Configuration.FirstOrDefault(f => f.Name == _uninstallElementName); } }

        private string UninstallXsltFilePath
        {
            get
            {
                return this.UninstallElement.GetAttributeValue(_xsltFilePathAttributeName);
            }
        }
    }
}
